acute triangle: a triangle with 3 acute angles
polygon: a closed plane figure with sides made from straight line segments
equilateral triangle: a triangle with all equal sides and angles
quadrilateral: a polygon with four sides.
hexagon: a polygon with six sides
rectangle: a parallelogram with all right angles
isosceles triangle: a triangle with two sides that are congruent
rhombus: a parallelogram with all sides the same length
obtuse triangle: a triangle with one obtuse angle
right trapezoid: a trapezoid with one right angle
octagon: a polygon with eight sides
right triangle: a triangle with one right angle
parallelogram: a polygon with two pairs of parallel sides
scalene triangle: a triangle with no sides the same length
pentagon: a polygon with 5 sides
square: a parallelogram with all sides the same length and all right angles
trapezoid: a quadrilateral with one set of parallel lines
kite: a quadrilateral where adjacent sides are congruent.